The present invention relates generally to methods and apparatus for controlling the operation of a portable electronic device, such as a portable radio, cassette player, voice recorder, or MP3 player. More particularly, the present invention relates to using a touchpad to control a portable electronic device.
As technology advances, portable electronic devices, such as portable radios, CD-players, voice recorders, and cassette tape players are becoming smaller, and are integrating an increasing number of functions. With the recent introduction of portable MP3 players, and other portable devices that play music from solid state memory or other digital storage, portable electronic devices may become still smaller, and even more complex to operate.
As used herein, a portable electronic device refers to one of a wide variety of small, portable consumer electronic devices that are primarily designed to perform specific predefined functions. Most of these devices are small enough to fit within a pocket, or be clipped onto a belt, though some, such as portable stereos that include speakers may be considerably larger. Many consumer audio devices such as portable radios, cassette players and recorders, portable CD players, voice recorders, and portable MP3 players are among the types of devices that are considered portable electronic devices for purposes of this application. Other portable entertainment devices, such as portable DVD players, as well as other portable electronic devices having specific predefined functions, such as pagers, remote controls, and cellular telephones may also be within the definition of a portable electronic device.
More complex devices, such as portable computers or personal digital assistants (PDAs), which provide general functionality or are extensively programmable are not within the definition of a portable electronic device, as used herein. Although such general purpose devices may include a capability to play audio from storage or from a CD, or may be programmed to perform other functions similar to those performed by portable electronic devices, these are not typically the predefined functions of the device, and are not the functions for which these general purpose devices were primarily designed. General purpose devices, such as portable computers and PDAs do not compete in the same market as portable electronic devices, do not typically include the same limited-purpose components and predefined functions, and do not face the same cost and usability concerns as portable electronic devices.
Typically, portable electronic devices include numerous buttons, switches, knobs, and displays to permit a user to control the operation of the device. All of these components take space on the housing of the device, and thereby limit the ability to reduce the size of the device. Reducing the size of these components may cause usability problems, since pressing tiny buttons and reading miniature displays may be awkward or irritating for many users. These problems are becoming more severe, since an increased number of integrated functions typically requires an increased number of buttons to control all of the functions.
The use of numerous small buttons and switches to control portable electronic devices also results in complex and inconvenient operation. Particularly, it may be difficult to find a desired button among the many buttons on such a device. Finding the correct button may be particularly difficult when attempting to operate the device without looking at it, as would be typical when the device is kept in a pocket, attached to a belt, or used during physical activity, such as jogging. Since these are among the major intended uses of portable electronic devices, this usability problem is a serious concern.
The use of numerous buttons to control these devices also increases the cost and decreases the manufacturing yield of the devices. Typically, assembly of the numerous buttons on a portable electronic device must be completed by hand, resulting in higher manufacturing costs and lower yields. Additionally, each button, switch, or knob is a separate mechanical component which may fail, reducing the manufacturing yield and the reliability of the devices.
Various input and control methods have been successfully used on other types of portable electronic equipment. On portable computers, input devices such as trackballs, touchpads, and control sticks have been used to control the movement of a cursor on a screen. Cursor movement may be used to control the operation of a variety of applications running on a portable computer. In personal digital assistants (PDAs), such as the PALMPILOT(trademark), a tradmark of Palm Computing, Inc. (a subsidiary of 3Com Corporation), of Santa Clara, Calif., which have some of the same size concerns as portable electronic devices, pen-based input and control is common. Typically, a stylus or pen is used to draw characters on a touch-sensitive screen to input the characters into the PDA without using a keyboard. Gestures, such a crossing out a word on the screen, or tapping the stylus over a graphical icon on the screen may be used to enter and edit text, or to control the operation of a typical PDA.
On portable computers, immediate visual feedback from the pointing device, typically provided in the form of cursor motion on a screen, is critical to operation of the computer. Without this feedback, the user would have no ability to determine where the cursor is located, and no ability to position the cursor over icons or other controls on the screen, which are used to control the operation of the portable computer.
PDAs, such as the PALMPILOT(trademark), while less reliant on immediate visual feedback than personal computers, still rely on the user being able to view a screen built into the PDA to control the operation of the PDA. Most operations on the PALMPILOT(trademark), for example, are specified by tapping a stylus over an icon or control that appears on the screen. Other gestures are used to enter and edit textxe2x80x94another activity that demands that a user view the screen to see the text that is being entered.
While this type of visual interface may be desirable for personal computers and PDAs, most portable electronic devices lack the type of display device that would permit such highly visual methods to be used. Additionally, users of most portable electronic devices are interested in operating the device with a minimal amount of difficulty. Ideally, a user should be able to operate the device quickly, easily, and without having to view a display while operating the device. Since methods of using touch-sensitive devices on personal computers and PDAs provide immediate visual feedback as an important part of their user interface, or require interaction with visual elements on a screen, they typically demand that a user view a display on the device while the device is being operated. This renders these methods unsuitable for use on a wide variety of portable electronic devices. Additionally, use of a stylus or pen to enter commands is unacceptable for most portable electronic devices, since attempting to use a pen while jogging or engaging in other physical activity would be nearly impossible for most users.
In view of the above, it would be desirable to provide a portable electronic device that is easy and convenient to use, even without looking at the device.
It also would be desirable to provide a portable electronic device with a reduced number of buttons disposed on its housing, thereby permitting the space on the device to be used for other purposes, such as providing a larger display, or reducing the size of the device.
It would further be desirable to provide a portable electronic device with reduced manufacturing costs, and higher yields.
It is an object of the present invention to provide a portable electronic device that is easy and convenient to use, even without looking at the device.
It is also an object of the present invention to provide a portable electronic device with a reduced number of buttons disposed on its housing, thereby permitting the space on the device to be used for other purposes, such as providing a larger display, or reducing the size of the device.
It is a further object of the present invention to provide a portable electronic device with reduced manufacturing costs, and higher yields.
These and other objects of the present invention are achieved by providing apparatus and methods for using a touchpad to control a portable electronic device, such as a portable radio, CD player, cassette tape player, voice recorder, pager, portable DVD player, or MP3 player. Instead of using a plurality of buttons disposed on the housing of the device for control, the present invention teaches use of a single touchpad, on which the user traces patterns to control the device. The device does not need to provide immediate visual feedback, and the patterns are simple enough that they may be entered without requiring that the user view the portable electronic device while entering the commands.
The portable electronic device of the present invention comprises a touchpad disposed on the housing of the device. A microcontroller within the device receives electrical signals from the touchpad, representing x-y coordinates of the location at which a user""s finger contacts the touchpad. Alternatively, the touchpad may send signals indicative of the motion of a user""s finger across the surface of the touchpad. The microcontroller compares the data received from the touchpad with a plurality of patterns stored in a memory coupled to the microcontroller.
Each of the stored patterns represents a command or function of the portable electronic device. If the microcontroller determines that the data received from the touchpad matches one of the patterns, the microcontroller causes the device to perform the command or function associated with the matched pattern.
In a preferred embodiment of the portable electronic device of the present invention, a pattern representing a function does not need to be matched precisely. A xe2x80x9cclosexe2x80x9d match, in which the pattern is scaled, translated, or rotated within preset bounds will be sufficient to indicate a match. Additionally, some variation in timing or speed at which a pattern is traced may be tolerated in the matching process.
The present invention also discloses a method for controlling a portable electronic device by receiving data from a touchpad, and comparing the data with a plurality of predefined patterns, each of which represents a function of the portable electronic device. If a matching pattern is found, the function represented by the matching pattern is performed.